Colorectal cancer screening: Opportunities to improve uptake, outcomes, and disparities

Colorectal cancer screening program implementation: biennial adherence and participation patterns

INTRODUCTION AND AIM

Adherence to colorectal cancer (CRC) screening is essential for the effectiveness of screening programs. Even though organized screening programs can improve the quality of the process and adherence, there are still challenges to overcome. The aim of the present study, in which we implemented a biennial organized screening program for CRC, was to describe adherence and participation patterns.

MATERIALS AND METHODS

A longitudinal, descriptive study was conducted, in which a team of trained patient navigators carried out interventions, with reminders via cellphone communication, to follow a cohort of 301 subjects eligible for CRC screening, utilizing a fecal immunochemical test (FIT). All the follow-up subjects received a FIT kit.

RESULTS

A total of 747 cellphone calls were made and divided into three interventions. From the initial cohort, 126 subjects completed their biennial screening process through the FIT, indicating a consistent adherence rate of 41.8% to our program. The participation patterns were: 126 consistent participants (41.8%), 160 inconsistent participants (53.2%), and 15 participants that were never contacted (5%).

CONCLUSIONS

In conclusion, our study underlines the importance of organized screening programs in the early detection of CRC. The implementation of follow-up interventions, through reminders and the training of patient navigators, can improve adherence, but there is a need for examining new strategies, to overcome barriers to communication via cellphone.

Improving colorectal cancer screening - consumer-centred technological interventions to enhance engagement and participation amongst diverse cohorts

The current "Gold Standard" colorectal cancer (CRC) screening approach of faecal occult blood test (FOBT) with follow-up colonoscopy has been shown to significantly improve morbidity and mortality, by enabling the early detection of disease. However, its efficacy is predicated on high levels of population participation in screening. Several international studies have shown continued low rates of screening participation, especially amongst highly vulnerable lower socio-economic cohorts, with minimal improvement using current recruitment strategies. Research suggests that a complex of dynamic factors (patient, clinician, and the broader health system) contribute to low citizen engagement. This paper argues that the challenges of screening participation can be better addressed by (1) developing dynamic multifaceted technological interventions collaboratively across stakeholders using human-centered design; (2) integrating consumer-centred artificial intelligence (AI) technologies to maximise ease of use for CRC screening; and (3) tailored strategies that maximise population screening engagement, especially amongst the most vulnerable.

AI and Clinical Decision Making: The Limitations and Risks of Computational Reductionism in Bowel Cancer Screening

Advances in artificial intelligence in healthcare are frequently promoted as ‘solutions’ to improve the accuracy, safety, and quality of clinical decisions, treatments, and care. Despite some diagnostic success, however, AI systems rely on forms of reductive reasoning and computational determinism that embed problematic assumptions about clinical decision-making and clinical practice. Clinician autonomy, experience, and judgement are reduced to inputs and outputs framed as binary or multi-class classification problems benchmarked against a clinician’s capacity to identify or predict disease states. This paper examines this reductive reasoning in AI systems for colorectal cancer (CRC) to highlight their limitations and risks: (1) in AI systems themselves due to inherent biases in (a) retrospective training datasets and (b) embedded assumptions in underlying AI architectures and algorithms; (2) in the problematic and limited evaluations being conducted on AI systems prior to system integration in clinical practice; and (3) in marginalising socio-technical factors in the context-dependent interactions between clinicians, their patients, and the broader health system. The paper argues that to optimise benefits from AI systems and to avoid negative unintended consequences for clinical decision-making and patient care, there is a need for more nuanced and balanced approaches to AI system deployment and evaluation in CRC.

Attributes Used for Cancer Screening Discrete Choice Experiments: A Systematic Review

BACKGROUND

Evidence from discrete choice experiments can be used to enrich understanding of preferences, inform the (re)design of screening programmes and/or improve communication within public campaigns about the benefits and harms of screening. However, reviews of screening discrete choice experiments highlight significant discrepancies between stated choices and real choices, particularly regarding willingness to undergo cancer screening. The identification and selection of attributes and associated levels is a fundamental component of designing a discrete choice experiment. Misspecification or misinterpretation of attributes may lead to non-compensatory behaviours, attribute non-attendance and responses that lack external validity.

OBJECTIVES

We aimed to synthesise evidence on attribute development, alongside an in-depth review of included attributes and methodological challenges, to provide a resource for researchers undertaking future studies in cancer screening.

METHODS

A systematic review was conducted to identify discrete choice experiments estimating preferences towards cancer screening, dated between 1990 and December 2020. Data were synthesised narratively. In-depth analysis of attributes led to classification into four categories: test specific, service delivery, outcomes and monetary. Attribute significance and relative importance were also analysed. The International Society for Pharmacoeconomics and Outcomes Research conjoint analysis checklist was used to assess the quality of reporting.

RESULTS

Forty-nine studies were included at full text. They covered a range of cancer sites: over half (26/49) examined colorectal screening. Most studies elicited general public preferences (34/49). In total, 280 attributes were included, 90% (252/280) of which were significant. Overall, test sensitivity and mortality reduction were most frequently found to be the most important to respondents.

CONCLUSIONS

Improvements in reporting the identification, selection and construction of attributes used within cancer screening discrete choice experiments are needed. This review also highlights the importance of considering the complexity of choice tasks when considering risk information or compound attributes. Patient and public involvement and stakeholder engagement are recommended to optimise understanding of unavoidably complex choice tasks throughout the design process. To ensure quality and maximise comparability across studies, further research is needed to develop a risk-of-bias measure for discrete choice experiments.

Examination of the Association Between Access to Care and Lung Cancer Screening Among High-Risk Smokers

Objective: The purpose of this study was to examine the influence of access to care on the uptake of low-dose computed tomography (LDCT) lung cancer screening among a diverse sample of screening-eligible patients. Methods: We utilized a cross-sectional study design. Our sample included patients evaluated for lung cancer screening at a large academic medical center (AMC) between 2015 and 2017 who met 2013 USPSTF guidelines for LDCT screening eligibility. The completion of LDCT screening (yes, no) was the primary dependent variable. The independent variable was access to care (insurance type, living within the AMC service area). We utilized binary logistic regression analyses to examine the influence of access to care on screening completion after adjusting for demographic factors (age, sex, race) and smoking history (current smoking status, smoking pack-year history). Results: A total of 1,355 individuals met LDCT eligibility criteria, and of those, 29.8% (n = 404) completed screening. Regression analysis results showed individuals with Medicaid insurance (OR, 1.51; 95% CI, 1.03-2.22), individuals living within the AMC service area (OR, 1.71; 95% CI, 1.21-2.40), and those aged 65-74 years (OR, 1.49; 95% CI, 1.12-1.98) had higher odds of receiving LDCT lung cancer screening. Lower odds of screening were associated with having Medicare insurance (OR, 0.30; 95% CI, 0.22-0.41) and out-of-pocket (OR, 0.27; 95% CI, 0.15-0.47). Conclusion: Access to care was independently associated with lowered screening rates. Study results are consistent with prior research identifying the importance of access factors on uptake of cancer early detection screening behaviors.

Biochemical assessment of the neurotoxicity of gold nanoparticles functionalized with colorectal cancer-targeting peptides in a rat model

The application of gold nanoparticle-peptide conjugates as theranostic agents for colorectal cancer shows much promise. This study aimed at determining the neurotoxic impact of 14 nm gold nanoparticles (AuNPs) functionalized with colorectal cancer-targeting peptides (namely p.C, p.L or p.14) in a rat model. Brain tissue samples, obtained from Wistar rats that received a single injection of citrate-capped AuNPs, polyethylene glycol-coated (PEG) AuNPs, p.C-PEG-AuNPs, p.L-PEG-AuNPs or p.14-PEG-AuNPs, and sacrificed after 2- and 12-weeks, respectively, were analysed. Inflammation marker (tumour necrosis factor-α, interleukin-6, interleukin-1β), oxidative stress (superoxide dismutase, catalase, glutathione peroxidase) and apoptotic biomarker (cytochrome c, caspase-3) levels were measured. Gold nanoparticle-treated groups sacrificed after 2-weeks did not exhibit any significant inflammatory, oxidative stress or apoptotic effects in brain tissue compared to the untreated control group. In brain tissue from rats that were exposed to citrate-capped AuNPs for 12-weeks, tumour necrosis factor-α and interleukin-6 levels were significantly increased compared to the untreated control. Exposure to PEG-AuNP, p.C-PEG-AuNP, p.L-PEG-AuNP and p.14-PEG-AuNP did not elicit significant toxic effects compared to the control after 12-weeks, as evidenced by the absence of inflammatory, oxidative stress and apoptotic effects in brain tissue. We thus report on the safety of PEG-coated AuNP-peptide conjugates for potential application in the diagnosis of colorectal cancer; however, exposure to citrate-capped AuNPs could induce delayed neuro-inflammation, and as such, warrants further investigation.

High Incidence of Burst Suppression during Propofol Sedation for Outpatient Colonoscopy: Lessons Learned from Neuromonitoring

Background

Although anesthesia providers may plan for moderate sedation, the depth of sedation is rarely quantified. Using processed electroencephalography (EEG) to assess the depth of sedation, this study investigates the incidence of general anesthesia with variable burst suppression in patients receiving propofol for outpatient colonoscopy. The lessons learned from neuromonitoring can then be used to guide institutional best sedation practice.

Methods

This was a prospective observational study of 119 outpatients undergoing colonoscopy at Thomas Jefferson University Hospital (TJUH). Propofol was administered by CRNAs under anesthesiologists' supervision. The Patient State Index (PSi™) generated by the Masimo SedLine® Brain Root Function monitor (Masimo Corp., Irvine, CA) was used to assess the depth of sedation. PSi data correlating to general anesthesia with variable burst suppression were confirmed by neuroelectrophysiologists' interpretation of unprocessed EEG.

Results

PSi values of <50 consistent with general anesthesia were attained in 118/119 (99.1%) patients. Of these patients, 33 (27.7%) attained PSi values <25 consistent with variable burst suppression. The 118 patients that reached PSi <50 spent a significantly greater percentage (53.1% vs. 42%) of their case at PSi levels <50 compared to PSi levels >50 (p=0.001). Mean total propofol dose was significantly correlated to patient PSi during periods of PSi <25 (R=0.406, p=0.021).

Conclusion

Although providers planned for moderate to deep sedation, processed EEG showed patients were under general anesthesia, often with burst suppression. Anesthesiologists and endoscopists may utilize processed EEG to recognize their institutional practice patterns of procedural sedation with propofol and improve upon it.

Barriers Driving Racial Disparities in Colorectal Cancer Screening in African Americans

PURPOSE OF REVIEW

Colorectal cancer screening has been shown to decrease mortality from colorectal cancer. Screening disparities continue to exist among ethnic minorities, particularly for African Americans. We herein review the barriers of colorectal cancer screening in this population.

RECENT FINDINGS

At its foundation are patient barriers, which are further compounded by physician-related barriers and the idiosyncrasies of the healthcare system. Interventions to address the barriers include patient outreach, provider education, and healthcare legislation addressing financial barriers. Recent research has focused on factors predicting intentions to undergo colorectal cancer screening. Underlying all of the barriers is the systemic racism that affects and influences the healthcare system as much as all other institutions and contributes to inequities in the delivery of effective cancer prevention efforts. Perpetual disparities in CRC screening within the African American community are due to multifactorial barriers from the individual patient to provider and healthcare system and societal influences. An awareness of the behavioral and systemic factors that affect African Americans must underpin efforts to reach full equity in delivering CRC screening to this often medically underserved segment of our society.

A national study of gender and racial differences in colorectal cancer screening among foreign-born older adults living in the US

This study examined within group heterogeneity in colorectal cancer screening (CRCS) among foreign-born individuals. Data were from the 2010, 2013 and 2015 National Health Interview Survey data on older adults (N = 5529). In 2018, multivariable logistic regression analysis was conducted to determine whether gender and race/ethnicity were associated with CRCS after controlling for sociodemographic, health access, and acculturation related factors. Overall, Asians were significantly less likely to report CRCS compared with Whites (aOR 0.63, CI 0.52-0.76). Hispanic race/ethnicity was negatively associated with CRCS among men (aOR 0.68, CI 0.50-0.91), but not women compared to white men/women, respectively. Additionally, factors associated with CRCS include having fair/poor health, usual source of care, insurance, ≥ 10 years of US residency and citizenship. Screening disparities experienced by these immigrants may be addressed by improving healthcare access, especially for noncitizens and those with limited healthcare access.

Faecal immunochemical testing implementation to increase colorectal cancer screening in primary care

Colorectal cancer (CRC) is the second leading cause of cancer death in USA, and CRC screening remains suboptimal. The aim of this quality improvement was to increase CRC screening in the internal medicine clinic (IMC) patients, between the ages of 50–75 years, from a baseline rate of 50%–70% over 12 months with the introduction of faecal immunochemical test (FIT) testing. We used the Plan–Do–Study–Act (PDSA) method and performed a root cause analysis to identify barriers to acceptance of CRC screening. The quality improvement team created a driver diagram to identify and prioritise change ideas. We developed a process flow map to optimise opportunities to improve CRC screening. We performed eight PDSA cycles. The major components of interventions included: (1) leveraging health information technology; (2) optimising team work, (3) education to patient, physicians and IMC staff, (4) use of patient navigator for tracking FIT completion and (5) interactive workshops for the staff and physicians to learn motivational interview techniques. The outcome measure included CRC screening rates with either FIT or colonoscopy. The process measures included FIT order and completion rates. Data were analysed using a statistical process control and run charts. Four hundred and seven patients visiting the IMC were offered FIT, and 252 (62%) completed the test. Twenty-two (8.7%) of patients were FIT positive, 14 of those (63.6%) underwent a subsequent diagnostic colonoscopy. We achieved 75% CRC screening with FIT or colonoscopy within 12 months and exceeded our goal. Successful strategies included engaging the leadership, the front-line staff and a highly effective multidisciplinary team. For average-risk patients, FIT was the preferred method of screening. We were able to sustain a CRC screening rate of 75% during the 6-month postproject period. Sustainable annual FIT is required for successful CRC screening.

Role of liquid biopsies in colorectal cancer

Colorectal cancer (CRC) is the third most common cancer worldwide, with a global incidence of over 1 million cases. In the era of personalized medicine, tumor sampling is essential for characterizing the molecular profile of individual tumors. This provides pivotal information regarding optimal sequencing of therapy and emergence of drug resistance, allowing for timely therapy adjustment. However, tumor tissue sampling offers static information in a single time point and area of disease at the time of biopsy, which may not entirely represent the heterogeneity of molecular alterations. Moreover, tumor biopsies often involve invasive procedures with potential risks to patients. Less invasive, safer, and real-time methods such as liquid biopsies have generated increasing interest as a surrogate of solid tumor biopsies. Liquid biopsy allows for noninvasive survey with detection of cell-free circulating tumor DNA (ctDNA) or circulating tumor cells. Blood-based assays are the most widely studied. Additionally, the quantity of ctDNA detected has been shown to correlate with tumor burden and enables assessment of tumor heterogeneity. In this article, we discuss the concept of liquid biopsies including ctDNA and circulating tumor cell, and their current application in the diagnosis and management of CRC. We suggest that liquid biopsies can be successfully used to characterize the molecular profile of CRC, monitor disease, detect minimal residual disease after surgery, and identify therapeutic targets and mechanisms of drug resistance. This strategy could potentially imply an early change in treatment, sparing unnecessary side effects, and minimizing health costs. Combined radiological and liquid biopsy assessments will likely become more standard in CRC oncology. However, large prospective studies are needed to definitively establish the role of liquid biopsy.

Identification of a specific peptide binding to colon cancer cells from a phage-displayed peptide library

BACKGROUND

New molecular probes are essential for early colon cancer diagnosis. A phage-display screening was performed to select novel binding peptides for early colon cancer imaging detection.

METHODS

A human colon cancer cell line (COLO320HSR) and a normal human intestinal epithelial cell line (NCM460) were used for subtractive screening with a phage peptide library. The positive peptides were identified, and their binding capacities were confirmed by confocal immunofluorescence both in human colon cancer cells and in biopsy specimens. The sequences were further analysed for homology and the existing mimotopes by the BLAST algorithm and the MimoDB database.

RESULTS

A peptide termed as CBP-DWS, which was demonstrated to be capable of binding to a panel of human colon cancer cell lines and tissues, was identified; it had virtually no binding to normal human intestinal epithelial cell line NCM460 and normal surrounding colon tissues. Bioinformatics analyses suggest that CBP-DWS targets human Glypican-3, which may be involved in important cellular functions in multiple cancer types.

CONCLUSIONS

These studies suggest that the selected peptide CBP-DWS may be a candidate to serve as a novel probe for colon cancer imaging.

Poly(HydroxyButyrate-co-HydroxyValerate) (PHBHV) Nanocarriers for Silymarin Release as Adjuvant Therapy in Colo-rectal Cancer

The aim of this study was to address one of the major challenges of the actual era of nanomedicine namely, the bioavailability of poorly water soluble drugs such as Silymarin. We developed new, biodegradable, and biocompatible nanosized shuttles for Silymarin targeted delivery in colon-cancer cells. The design of these 100 nm sized carrier nanoparticles was based on natural polymers and their biological properties such as cellular uptake potential, cytotoxicity and 3D penetrability were tested using a colon cancer cell line (HT-29) as the in vitro culture model. Comparative scanning electron microscopy (SEM) and atomic force microscopy (AFM) measurements demonstrated that the Silymarin loaded Poly(3-HydroxyButyrate-co-3-HydroxyValerate) (PHBHV) nanocarriers significantly decreased HT-29 cells viability after 6 and 24 h of treatment. Moreover, in vivo-like toxicity studies on multicellular tumor spheroids showed that the Silymarin loaded PHBHV nanocarriers are able to penetrate 3D micro tumors and significantly reduce their size.